BUG fix deprecation of limit and fill_method in pct_change

doc/source/whatsnew/v2.2.0.rst

@@ -269,7 +269,7 @@ Other Deprecations
 - Deprecated the option ``mode.data_manager`` and the ``ArrayManager``; only the ``BlockManager`` will be available in future versions (:issue:`55043`)
 - Deprecated the previous implementation of :class:`DataFrame.stack`; specify ``future_stack=True`` to adopt the future version (:issue:`53515`)
 - Deprecating downcasting the results of :meth:`DataFrame.fillna`, :meth:`Series.fillna`, :meth:`DataFrame.ffill`, :meth:`Series.ffill`, :meth:`DataFrame.bfill`, :meth:`Series.bfill` in object-dtype cases. To opt in to the future version, use ``pd.set_option("future.no_silent_downcasting", True)`` (:issue:`54261`)
--
+- Reverted deprecation of ``fill_method=None`` in :meth:`DataFrame.pct_change`, :meth:`Series.pct_change`, :meth:`DataFrameGroupBy.pct_change`, and :meth:`SeriesGroupBy.pct_change`. Now the keyword ``fill_method`` not being ``None`` and the limit keyword are deprecated. (:issue:`53491`)
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_220.performance:

pandas/tests/frame/methods/test_pct_change.py

@@ -143,15 +143,13 @@ def test_pct_change_with_duplicated_indices(fill_method):
         {0: [np.nan, 1, 2, 3, 9, 18], 1: [0, 1, np.nan, 3, 9, 18]}, index=["a", "b"] * 3
     )
 
-    if fill_method is not None:
-        msg = (
-            "The 'fill_method' keyword being not None and the 'limit' keyword in "
-            "DataFrame.pct_change are deprecated"
-        )
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = data.pct_change(fill_method=fill_method)
-    else:
-        result = data.pct_change(fill_method=None)
+    warn = None if fill_method is None else FutureWarning
+    msg = (
+        "The 'fill_method' keyword being not None and the 'limit' keyword in "
+        "DataFrame.pct_change are deprecated"
+    )
+    with tm.assert_produces_warning(warn, match=msg):
+        result = data.pct_change(fill_method=fill_method)
 
     if fill_method is None:
         second_column = [np.nan, np.inf, np.nan, np.nan, 2.0, 1.0]

pandas/tests/series/methods/test_pct_change.py

@@ -100,15 +100,13 @@ def test_pct_change_with_duplicated_indices(fill_method):
     # GH30463
     s = Series([np.nan, 1, 2, 3, 9, 18], index=["a", "b"] * 3)
 
-    if fill_method is not None:
-        msg = (
-            "The 'fill_method' keyword being not None and the 'limit' keyword in "
-            "Series.pct_change are deprecated"
-        )
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            result = s.pct_change(fill_method=fill_method)
-    else:
-        result = s.pct_change()
+    warn = None if fill_method is None else FutureWarning
+    msg = (
+        "The 'fill_method' keyword being not None and the 'limit' keyword in "
+        "Series.pct_change are deprecated"
+    )
+    with tm.assert_produces_warning(warn, match=msg):
+        result = s.pct_change(fill_method=fill_method)
 
     expected = Series([np.nan, np.nan, 1.0, 0.5, 2.0, 1.0], index=["a", "b"] * 3)
     tm.assert_series_equal(result, expected)